neck, counter for songs and poems
首 centers on the head and neck area, the topmost part of the body. The counter for songs and poems extends naturally from the idea of a head or beginning, as in counting the first items or stanzas.
首 is a pictograph of a head with hair or a headdress on top, emphasizing the neck and head area. The modern form retains the eye-like 自 at the top and the lower strokes suggesting the neck.
The top part 自 looks like an eye with a nose, and the lower strokes resemble a neck and shoulders. Together they form the head and neck: 首.
For シュ, imagine a shoe hanging around a neck: shoe -> シュ, and the neck is where you'd hang it.
neck
prime minister; chancellor (Germany, Austria, etc.); premier
nipple; teat
capital (city); metropolis
wrist
head; leader; top
party leader
first place; head position; leading position
ankle
head (of organization, organisation); chief
plotting; planning (crime, intrigue)
surrender (to the authorities); giving oneself up; turning oneself in
head; chief; boss; leader
sovereign; ruler; head of state
death by hanging; execution by hanging
beginning and end; from beginning to end
necklace; choker
nose (of plane)
radical (of a kanji character)
head; leader; prime minister
(death by) hanging
one tanka; one poem
executives; top management; governing body
Greater Tokyo Metropolitan area